OBJECTIVE: To
analyze the validation, internal consistency and reliability of the satisfaction
scale for performing physical activity among Brazilian adults.METHODS:
The satisfaction scale for the performance of physical activity was applied
using a multidimensional questionnaire. Face-to-face interviews were performed
with 1,461 subjects (63.7% females) who were at least 18 years in Curitiba,
Southern Brazil from April 2009 to July 2009. The questionnaire was submitted
to an analysis of its validity (factorial and construct) and reliability (internal
consistency and temporal stability). The test-retest procedure was used to assess
temporal stability after a one-week interval (n = 74).RESULTS:
The exploratory factor analysis yielded two main factors: satisfaction with
the practice of walking during leisure-time and satisfaction with the practice
of moderate or vigorous physical activity. These factors explained 29.3% of
the variance for walking and 53.5% of the variance for moderate and vigorous
physical activity. Alpha values of 0.91 and 0.88, respectively, indicated high
internal consistency and two subscales. The scale items presented high agreement
in the test-retest for both walking (71.7% to 81.1%) and moderate and vigorous
physical activity (80.5% to 92.6%). These factors presented a significant correlation
with time spent walking (minutes/week) (rho = 0.23; p < 0.001) and time spent
performing moderate and vigorous physical activity (rho = 0.21; p < 0.001),
which indicated the validation of the construct.CONCLUSIONS: The proposed satisfaction scale for the performance of physical
activity has been appropriately validated and exhibits internal consistency
and reliability for Brazilian adults.

Physical activity (PA) is an important component of a healthy
life and confers various physical and psychological benefits.a
Levels of physical activity in adults, however, have decreased in
recent decades.12 Physical inactivity is associated
with various morbidities, including hypertension 17
and other cardiovascular diseases and diabetes 10.
Therefore, interest in the promotion of PA has increased in an
effort to reduce the negative impacts of physical
inactivity.10

To date, low adherence to programs that promote PA has limited
their results. Factors such as weather, poor support from family
and friends, lack of time and motivation, low quality of public
spaces and financial difficulties have been reported to be
barriers of PA.2,26 In contrast, personal satisfaction
and the possibility of social interaction can have a positive
influence on promoting PA.20,26 The perception of
satisfaction (i.e., enjoyment) seems to be an important mediator
of motivation for PA, and substantially contributes to active
physical behavior.1,5,8

Studies conducted with adolescents 5 and adults
8,22 have reported that individuals who are more
satisfied with PA are more active. Our literature review did not
reveal any studies of the psychosocial aspects of PA that made
reference to satisfaction among Brazilian adults. This gap in the
literature can be partially attributed to the lack of quality
psychometric instruments that are appropriate for the Brazilian
sociocultural context. To better understand the role of
psychosocial aspects in promoting PA, we need to develop
instruments that allow us to evaluate the relationship between
personal satisfaction and PA.

The present study aimed to validate and test the reliability
of the satisfaction scale for physical activity (SSPA) among
Brazilian adults.

METHODS

The data analyzed in the present study were taken from a
project designed to designed to evaluate various aspects of the
health, lifestyle and leisure habits of the population residing
close to parks and plazas in the city of Curitiba, Southern
Brazil, from April 2009 to July 2009. Parks and plazas were
selected according to the socioeconomic conditions of the
neighborhood where they were located and the environmental
quality.19

All street segments in a 500-m radius around the parks and
plazas selected for the study (n = 1,899), and all domiciles in
these segments were enrolled. Only the segments that contained at
least one domicile (n = 1,538) were considered eligible. Using
the EpiInfo software, a table of random numbers was generated for
a lottery that selected one domicile per segment. In our visits
to these domiciles, the interviewers used a similar lottery to
randomly choose one eligible resident from each domicile to be
interviewed, according to the methodology proposed by
Kish.11

Individuals aged 18 years or older who had resided in the
domicile in question for at least one year were considered
eligible. The individuals who did not reside in the domicile
(e.g., maids and visitors) were excluded. In addition, we
excluded individuals with physical limitations that prevented
them from performing PA or who had any cognitive limitations that
would make it difficult for them to understand the
questionnaire.

During the data collection process, 25 interviewers (all at
least 18 years) who had completed their high school education
received 30 hours of theoretical and practical training on the
distribution, completion and codification of the questionnaire.
The interviewers were instructed to conduct the interviews in an
appropriate location within the domicile to avoid the influence
of other family members. Interviews were conducted in 95% (n =
1,461) of the eligible segments;the interviewers did not
encounter any eligible residents in the remaining segments (5%).
In addition, 7.9% (n = 121) of the residents refused to
participate. Quality control was performed by field supervisors
who redid the interviews for 12.5% of the same sample.

Reliability was tested through repeated interviews conducted
for a subsample of individuals who were selected in a systematic
and random manner from the participants used in the first stage
of the data collection. For every five subjects interviewed, one
was invited to participate in a second interview but only 74
people accepted to be interviewed twice. The second interviews,
which were conducted after an interval of seven to ten days, were
performed over the phone by the field supervisors.

To evaluate satisfaction regarding the performance of PA, we
used a translated and adapted version of the original scale
developed by San Diego State University (USA), which was used in
the Neighborhood Quality of Life Study,b The original tool
consisted of six questions related to satisfaction with moderate
and vigorous physical activity (MVPA), which were evaluated
separately. The responses were communicated using a 5-point
Likert scale.

In the present study, the SSPA was tested with reference to
two items (divided by blocks) using questions about satisfaction
resulting from walking and MVPA. We opted to analyze these
psychometric characteristics separately for PA of different types
and intensity levels because the perception of satisfaction is
distinct for each case. Walking is a common human activity,
whereas MVPAs involve more complex motor actions and greater
intensity.

Each block was composed of three questions: The first block
addressed satisfaction related to walking: 1) Do you enjoy
walking in your free time? 2) Do you feel good while walking in
your free time? 3) Do you feel well after walking in your free
time? The second block addressed satisfaction related to MVPA: 4)
do you like to practice moderate or vigorous activity in your
free time? 5) Do you feel well while participating in moderate or
vigorous activity in your free time? 6) Do you feel well after
participating in moderate or vigorous activity in your free
time?

The questions were
applied in a sample of adults with low, medium and high levels of education
(n = 20) to verify clarity and comprehension regarding the order and form of
the scales. During the interviews, we observed that subjects with lower levels
of education presented greater difficulty understanding the questions. Thus,
we adapted the original 5-point scale into a 3-point scale (the choices were
no, a little or a lot). The difficulty that some individuals experienced with
the original scale was understandable given the differences between the sociocultural
characteristics of Brazil and those of other countries with higher levels of
education. In addition, domiciliary interviews using complex psychometric scales
are more common in North American countries than in Brazil. The adapted SSPA
used in the present study is presented in the Appendix.

A 3-point scale was used ("no", "a little" and "a lot"). The
scores were computed using the sum of the responses for each
block, and two scores varying from zero to six points were
generated to indicate greater or lesser satisfaction with either
walking or MVPA.

Physical activity was evaluated using the leisure module from
the long version of the International Physical Activity
Questionnaire,4 which was appropriately adapted for
the Brazilian population.15 The questions were
designed to determine whether the participants spent at least ten
minutes walking and engaging in MVPA per week, and the
questionnaire required that the participants indicate the
duration of activity. The information on MVPA was grouped and
analyzed separately from the information on walking so that the
SSPA questions could be compared in a specific manner.

Gender, age, socioeconomic level and self-perceptions
regarding health were also considered in the questionnaire.
Socioeconomic status was evaluated according to the criteria for
economic classification in Brazil c. The classes were grouped
into A (A1+A2, wealthier), B (B1+B2) and C (C+D+E, poorer).
Health self-perception was evaluated using the following
question: "How do you consider your health?" The response options
were given using a 4-point Likert scale (bad, regular, good and
very good). The "good" and "very good" responses were grouped
together to create a variable called "positive health
perception".d

The structure of the scale was verified using exploratory
factor analysis, and varimax rotation was used to verify
the load of each item. Sampling adequacy was tested with the
Kaiser-Meyer-Olkin (KMO) method. Eigenvalues
> 1.0 and items with a load > 0.4
were deemed acceptable.

To validate the SSPA construct, we compared the sum of the
scores for walking and MVPA with the weekly time dedicated to
those activities. For this purpose, we used Spearman (rho)
rank-order correlation. In this analysis, we assumed that a
positive and specific association existed between the scale
scores and PA (e.g., minutes/week of walking and the satisfaction
score associated with walking). This method was intended to
indicate the meaning of the relationship rather than demonstrate
a positive correlation between the variables.

Reliability was evaluated by determining internal consistency
(Cronbach's a) and temporal stability (intraclass correlation
coefficient - ICC), with the latter evaluated using the
test-retest method. Values for a and ICC
> 0.70 were considered acceptable
reliability.25 All analyses were performed using the
SPSS 15.0 software, and the required significance level was
5%.

The individuals were informed about the research procedures
and voluntarily agreed to participate. The study was approved by
the Committee of Ethics in Research of Escola Superior de
Educação Física da Universidade Federal de
Pelotas (protocol nº 005/2008) on 12/17/2008.

RESULTS

Table
1 shows the characteristics of the interviewees (n = 1,461) and the subsample
used to determine temporal stability (n=74). A high proportion of the participants
in the overall sample (49.6%) were at the intermediate socioeconomic level (B).
In addition, 69% reported positive perceptions regarding their own health, and
61.7% and 76.2% did not practice walking or MVPA, respectively, in their free
time. The subsample used to determine temporal stability presented characteristics
similar to those of the overall sample for all variables examined in the present
study.

The exploratory
factor analysis identified two independent, significant factors with eigenvalues
> 1.0. The combination of the two factors was able to explain 82.8% of
the total variance. Factor 1 consisted of three items regarding satisfaction
with walking (variance = 29.3%). Factor 2 (variance = 53.5%) also consisted
of three items, but these were related to MVPA. All items presented load at
>0.84 in the respective factor (Table 2). The present
sample was adequately large enough for the procedures employed during the factor
analysis (KMO = 0.74; p < 0.001).

The internal consistency
(Cronbach's a) was significant for all items (Table
3), and the values were high for walking (a=0.91)
and MVPA (a=0.88). All items were important in explaining
the total variance of each factor; however, only the first MVPA item could positively
alter the total a if the item was removed from the
scale. Moreover, this alteration would not create a significant increase in
the final value. Thus, the item was kept because the total a
value was high (a=0.88).

We observed a significant positive correlation between the
factors mentioned and the PA indicators for both walking (rho =
0.23; p < 0.001) and MVPA (rho = 0.21; p < 0.001). We also
observed that the SSPA score for walking was not correlated with
the number of minutes of MPVA or with the SSPA score for MVPA.
The results indicate a relationship between higher levels of
satisfaction with PA and greater time spent engaging in PA. This
association was specific to the type of PA (walking versus
MVPA).

The results of
the temporal stability analysis are presented in table 4.
The ICC values were 0.71 for walking (95%CI: 0.49;0.83) and 0.75 for MVPA (95%CI:
0.53;0.87). The concordance was high for all scale items for both walking (71.7%
to 81.1%) and MVPA (80.5% to 92.6%).

DISCUSSION

The SSPA proposed in the present study showed psychometric
characteristics adequate for its use in studies of Brazilian
adults.

The results of
the SSPA application suggest that the intensity and type of PA must be considered
to analyze perceptions regarding PA satisfaction. Indeed, the issues of walking
and MVPA satisfaction are distinct.26 The exploratory factor analysis
(Table 2) suggests that two independent factors explain the
total variance. The first factor, which was related to walking satisfaction,
presented a high load of factors (between 0.84 and 0.92). The same result was
observed for MVPA (the second factor), which had a load between 0.89 and 0.93;
however, the variance was greater for MVPA (53.5% versus 29.3% for walking
satisfaction). The factor structure was different from that of the original
scale, which was only used to analyze MVPA.21

In general, the individuals presented distinct perceptions
regarding their "enjoyment" of PA at different levels of
intensity. For example, many individuals enjoyed walking but did
not indicate that they received satisfaction from vigorous
physical activities, such as running and sport practices. Two
recent surveys of PA in adults suggested that men are more active
and spend more time engaged in MVPA.7,14 In part, this
may be explained by the greater demand for vigorous activity
among men. In contrast, women tend to practice less intense
PA.13 In addition to differences in biology, cultural
considerations are also different for men and women. For example,
women are raised to care about their families from an early age,
whereas men are more oriented toward manual labor and other
activities that require more vigorous physical
activity.24

The internal consistency
of the scales for both walking (a = 0.91) and MVPA
(a = 0.88) was adequate25 and similar
to that of other studies.18,23,27 The a
value was > 0.70 for all the scale items, which shows that all items make
an important contribution, and each scale has a consistent structure (Table
3). Other studies that have investigated the psychometric characteristics
of PA satisfaction in children3 and adolescents16 found
high reliability values (a = 0.85)3 that
were similar to those of the present study. Using a scale with 18 items, Heesch
et al. tested the psychometric characteristics of PA satisfaction in a study
of 378 adults between the ages of 25 and 75 years old and attained a value of
a=0.95,9 The higher number of items on
the scale of Heesch et al's study can explain the high a
value,9 as the number of items of the tool directly influences that
value.

In our analysis of the correlation between the SSPA factors
and PA indicators, we expected that the individuals with the
highest satisfaction scores would present positive PA indicators
(even though satisfaction is not the only variable that explains
PA).26 We found that satisfaction related to walking
and MVPA exhibited a positive moderate correlation with time
spent on those activities.

The reliability results were positive (71.7% to 92.6%).
Although the second interview was conducted by phone, this did
not seem to significantly alter the reliability results. These
values were similar or even greater than those reported by
studies of psychosocial scales for PA.3,6,16

Despite the effort made in the present study to validate and
test the reliability of the SSPA in Brazilian adults, some
limitations need to be considered. The scale was tested using a
sample of adults who were residents of the city of Curitiba.
Sixty-two percent of the study participants were from high
socioeconomic levels, and 69% exhibited positive perceptions of
their health. Research in other locations must also consider
socioeconomic status and individual health perceptions when
comparing and analyzing their results. Importantly, our
reliability results were significant and satisfactory. We
performed self-reported measurements, however, which present a
less precise estimation of PA. Nonetheless, the patterns of PA
(more or less time spent performing PA) were adequate for us to
compare with the scale scores.

Based on the results shown in the present study, we can
confirm the validity of the SSPA model, which exhibited internal
consistency and reliability that is sufficient to evaluate
satisfaction regarding the performance of walking and MVPA among
Brazilian adults.